Carbon set



P 1938- s. H. LINDERMAN 2,131,381

CARBON SET Filed June 5, 1936 INVENTOR 575mm [mam/my ATTORNEY Patented Sept. 27, 1938 UNITED STATES PATENT OFFICE CARBON SET Application June s, 1936, Serial No. 83,665

5 Claims.

This invention relates to carbon sets and with regard to certain more specific features thereof to a folded-sheet carbon set; that is, a single sheet of paper which is treated and folded to function in the manifolding of invoices and statements or any other desired forms.

It is an object of the invention to provide a relatively inexpensive one piece carbon set having provision for easy assembly with three or more work sheets and having provision for stepping-up the transfer action at the rear of the set.

Another object of the invention is to provide a transversely folded carbon sheet, having the stepping-up action previously mentioned, with means for easily determining the line of transverse fold and for avoiding in the use of the set, the incorrect positioning of the carbon sheet, the soiling of the operator's hands and the transfer of any of the carbon coating to parts of the machine.

Other objects will be obvious from a consideration of the following description.

In the accompanying drawing, wherein is shown one of various possible embodiments of the invention,

Figure 1 is a view in bottom plan of a carbon treated sheet adapted to be folded into the carbon set contemplated by the invention,

Figure 2 is a view in top plan of the same sheet,

Figure 3'is a view of the treated sheet as shown in Figures 1 and 2 folded as a carbon set ready for use in a typewriter or other business machine, and

Figure 4 is a fragmentary view of the folded set.

It is to be noted that the sheets shown in the drawing may be produced by the cutting of webs previously treated with carbon compositions or the separate sheets there shown may be individually treated. For the purposes of this invention it will be sufiicient to describe the sheets as individually treated.

A sheet of suitable paper stock is indicated at In having opposite side edges l l and opposite end edges I-2. The sheet is illustrated in Figures 1 and 2 in flat condition, and referring particularly to Figure 2, an area l3 at the right end of the sheet extending from one end edge l2 to a transverse line l4 near the middle line of the sheet is coated with a carbon composition having a relatively soft carbon characteristic. The remaining area of the sheet indicated at I5 is untreated.

On the reverse side of the same sheet, as indicated in Figure 1, the area [B at the left end of the sheet is similarly treated with a carbon composition but one having a relatively harder carbon characteristic. This coated area It extends from the opposite end edge l2 to a line ll near the middle line of the sheet. An untreated path l8 extends transversely of the sheet between the two carbon treated areas and preferably this path I8 is slightly offset from the exact middle line of the sheet so that in making a transverse fold of the sheet preferably along the middle line of the path the untreated carbon area I5 is presented with its edge l2 slightly above the end I! of the other part of the fold. Thus, the underlying extending margin IQ of the folded section at the rear of the set provides a guide for the entry of the first copy sheet into the set and determines the proper position of the set for use in assembling the work sheets.

Figure 3 of the drawing shows the relation of the hard carbon treated area to the soft carbon treated area when the set is used for manifolding. The original form is backed against the untreated area l5. A first copy form is inserted within the 7 fold between the hard carboned surface l6 at the front and the untreated area at the rear. A sec ond copy form is applied to the set at the rear of the soft carboned area l3. The untreated section l8 at the fold of the set allows for clean handling and introduction of the set into the machine without any of the carboned surfaces being exposed.

By the present invention a single folded and carbonv treated sheet may be used to make several copies, and the transfer to the later copies in the set is stepped up to compensate for the limitations imposed by the added sheets of paper. Although the drawing herewith shows only a single transverse fold of asheet it is obvious that a. longer sheet may be employed with additional reverse folds and progressively softer carbon coatings.

What is claimed is:-

1. A one piece carbon set comprising a transversely folded sheet with a front fold having an uncoated front surface and a rear surface of a relatively hard carbon coating, the rear fold of the sheet having an uncoated front surface and a rear surface of a relatively soft carbon coating, and an uncoated section at the line of fold.

2. A one piece carbon set comprising a transversely folded sheet with a front fold having an uncoated front surface and a rear surface of a relatively hard carbon coating, the rear fold of the sheet having an uncoated front surface and a rear surface of a relatively soft carbon coating, the front folded section being shorter than the rear folded section.

3. A manifolding sheet, one side of which has an area extending from one end edge to a line coated area of a relatively hard carbon formula terminating at a transverse line short of the transverse median of the sheet, and the other side of which has a coated area of a relatively soft carbon formula terminating at a transverse line beyond the transverse median of the sheet, and a transverse path of non-carboned sheet between the said lines of termination of the coated areas.

5. A manifolding sheet one side of which has a coated area of a relatively hard carbon formula terminating at a transverse line short of the transverse median of the sheet, and the other side of which has a coated area of a relatively soft carbon formula terminating at a transverse line beyond the transverse median of the sheet, a transverse path of non-carboned sheet between the said line of termination of the coated areas, and a fold at the said path, parallel therewith, by which the shorter area with its hard carbon surface is caused to overlie the longer portion of the sheet when folded.

STEWART H. LINDERMAN. 

